The present invention relates to a method of manufacturing a pair of terminals, one of which can be inserted into the other by a reduced force so as to be connected to the latter.
FIG. 8 shows a conventional pair of a male and a female terminals 21 and 14 which can be connected to each other by inserting the male terminal 21 into the female one 14. The female terminal 14 is manufactured by punching and bending an electroconductive metal plate not shown in FIG. 8, and has an electric wire connecting portion 15 and a male terminal connecting portion 16. The male terminal connecting portion 16 includes a tubular body 17 having a quadrangular cross section, and an electric contact part 18 which is an elastic part bent at an obtuse angle and continuous to the tubular body 17 and is located inside the tubular body 17. The tubular body 17 has an electric contact projection 20 opposed to the top 19 of the electric contact part 18. The electric contact portion 22 of the male terminal 21, which is a flat plate-like portion, is inserted into the tubular body 17 of the female terminal 14 between the electric contact part 18 and the electric contact projection 20 thereof so that the terminals are connected to each other. The front part of the electric contact portion 22 of the male terminal 21 has slopes 23 for facilitating the insertion of the terminal into the female one 14. The male terminal 21 has an electric wire connecting portion which is the rear portion of the terminal. The male and female terminals 21 and 14 are plated with tin, nickel or the like so that the terminals are prevented from rusting. The terminals 21 and 14 are provided in the housings of a male and a female connectors not shown in FIG. 8, so that the terminals are connected to each other when the connectors are coupled to each other. Since the number of the terminals of each of connectors has recently become large, a force necessary to insert all the male terminals 21 into all the female terminals 14 or couple the connectors to each other, especially a force necessary for the initial stage of the insertion, has become so high that the force exceeds a human engineering limit of about 10 Kg for a work man and it is harder for him to couple the connectors to each other. This is a problem.